Although advertising in newspapers, in magazines and on television are effective to induce people to buy a product, point of purchase advertising is probably the most effective advertising technique known. By "point of purchase" advertising is meant advertising which reaches the potential buyer at the time and in the place he can actually purchase the product being advertised.
Retailers know the power of point of purchase advertising, and commonly use a variety of point of purchase advertising techniques, such as store front displays, in-store displays, salesmen, in-store video promos, and the like, to increase sales. Although voice messages directed at potential purchasers may be the most effective point of purchase advertising technique, many small retailers cannot afford to pay salesmen to work the retail floor and interest potential customers in purchasing products.
Devices which automatically generate a prerecorded audio message in response to the sensing of the presence of a person are, in general, known. U.S Pat. No. 3,509,288 to Leventhal, for example, discloses a point-of-purchase advertising system which senses the presence of a person by detecting rapid changes in the intensity of ambient light striking a photocell. When person's presence is detected, a tape player is activated to deliver a magnetically prerecorded message. The end of the prerecorded tape is sensed by an optical sensor, and the system is reset in response to the end-of-tape condition.
Cam Industries, Inc. of Topeka, Kansas sells a "cam-talker" device which automatically plays a taped message when a shopper walks by a point-of-purchase display. An ordinary tape recorder is used to record several messages on a continuous tape. Three-second pauses are left on the tape between recorded messages. The "cam-talker" device starts the tape when it senses the presence of a person nearby. The "cam-talker" device automatically senses the pause on the tape at the end of the message and automatically stops the tape before the next message begins playing.
Anheuser Busch, Incorporated, in conjunction with Solarts, Inc. of Colorado Springs, Colorado, sells a cooler door chime which is adapted for installation on the door of a beer cooler. When the cooler door is opened, a motion detector within the device controls an integrated circuit to generate a musical "jingle".
U.S. Pat. No. 4,117,461 to Kiebala discloses a device adapted for installation within a refrigerator which senses the removal of food from the shelves of the refrigerator and responsively activates a tape recorder. The tape recorder plays a prerecorded message encouraging dieting.
U.S. Pat. No. 4,023,151 to Markham discloses a device which uses photocells to sense the passage of a person over a doorstep, and actuates a tape player to play a prerecorded audio message reminding the departing person to perform certain tasks prior to leaving the house (e.g., lock the door or turn off the iron). A prerecorded end-of-message tone recorded on the tape at the end of the prerecorded message is decoded by a tone detector, turning the system off.
U.S. Pat. No. 4,544,920 to Hamlin discloses an intruder detection system which detects noise made by an intruder and activates a tape player which plays a tape recording of a barking dog or other building occupancy sounds. An endless loop tape cassette is used to avoid having to rewind the tape.
U.S. Pat. No. 4,366,873 to Levy et al discloses an electronic scale which synthesizes voice messages in response to measured weight, information inputted to the scale via a keyboard, and prestored digital information.
There is a need for a point-of-purchase audio advertising device which accurately and reliably detects the presence of a person but which does not continuously play back audio messages. The point-of-purchase advertising device should be sensitive enough to detect whenever a shopper passes nearby. Yet, a point-of-purchase advertising device having great sensitivity may constantly sense passersby when the retail floor is crowded, causing continuous playback of the prerecorded messages.
A shopper must remain within hearing range of the message being played for the message to be effective. A message which plays continuously isn't nearly as effective as one which is played especially for a shopper in response to the shopper's presence--since a person may be more interested in a message which he realizes is being played just for him. Prior art point of purchase advertising devices behave unpredictably and/or continuously play messages when operated in a crowded store--the best place to use such devices.
Purchasers and users of a point-of-purchase advertising device also often wish to use an unmodified, conventional tape recorder for recording and playing back prerecorded messages. Conventional cassette tape recorders are readily available and relatively inexpensive, thus decreasing the cost of the point-of-purchase advertising device. High-quality recordings including mixed voice, music and sound effects can be made using conventional cassette recording equipment to improve the effectiveness of the advertising.
However, the point-of-purchase advertising device must control the conventional tape recorder with absolute reliability, and should also be adaptable for use with any of a variety of different types of tape recorders. Different tape recorders have different critical characteristics, such as the amount of electronic noise they generate and the speed at which they start and stop. Because of these differences, a prior art point-of-purchase advertising device may work well with some tape recorders and yet control other tape recorders in an unreliable or unpredictable manner. There is therefore a need for a point-of-purchase advertising device which accurately controls virtually any type of tape recorder.